Polycarbonate resin composition

Abstract

Disclosed is a novel polycarbonate which has (1) a repeating unit (I) represented by the general formula: <IMAGE> and a repeating unit (II) represented by the formula: <IMAGE> (all the symbols are as defined in the claims); (2) a trihalogenophenoxy group as the end group thereof; and (3) a viscosity average molecular weight of 10,000 to 50,000, and 1 to 10 mol % of the repeating unit (I) in the main chain. The polycarbonate is excellent in all of flame retardance, impact resistance, and a thermostability at molding. Accordingly, the polycarbonate of the present invention is extensively and effectively used as various industrial materials such as home electric appliances, office automation devices, construction materials and the like.

What is claimed is: 
     
       1. A polycarbonate resin composition comprising (A) 100 parts by weight of a polycarbonate comprising (1) a main chain comprising a repeating unit (I) represented by the formula: ##STR12## wherein X 1  to X 4  are each a halogen atom, and a repeating unit II represented by the formula: ##STR13## (2) a trihalogenophenoxy group represented by the formula: ##STR14## wherein X 5  to X 7  are each a halogen atom, as the end group thereof; and   said polycarbonate having a viscosity average molecular weight of 10,000 to 50,000 and the repeating unit (I) in the main chain is in a proportion of 1 to 10 mol %; and (B) 1 to 10 parts by weight of a halogen-containing flame retarder having a halogen content of 30% by weight or more.                 TABLE 3                                                     
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       Poly-    Poly-     Halogen-containing                              
       carbonate                                                          
                carbonate Flame Retarder                                  
No.      (PC-1)     (PC-2)    BC-52*.sup.7                                
                                      EC-36*.sup.8                        
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Example 8                                                                 
         100         0        4.7     0                                   
Comparative                                                               
         100         0        12      0                                   
Example 6                                                                 
Example 9                                                                 
         100         0        0       4.4                                 
Comparative                                                               
         100         0        0       12                                  
Example 7                                                                 
Example 10                                                                
          0         100       3.3     0                                   
Comparative                                                               
          0         100       12      0                                   
Example 8                                                                 
Example 11                                                                
          0         100       0       3.0                                 
Comparative                                                               
          0         100       0       12                                  
Example 9                                                                 
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                                    Total                                 
                          Flame     Light-                                
       Flow    Izod Impact                                                
                          Retardance                                      
                                    trans-                                
         Value*.sup.9                                                     
                   Resistance*.sup.10                                     
                              1/16 1/32 mittance                          
No.      (ml/sec)  (kg/cm-cm) inch inch (%)                               
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Example 8                                                                 
         2.7 × 10.sup.-2                                            
                   81         --   V-0  90                                
Comparative                                                               
         3.5 × 10.sup.-2                                            
                   13         --   V-0  88                                
Example 6                                                                 
Example 9                                                                 
         2.9 × 10.sup.-2                                            
                   83         --   V-0  90                                
Comparative                                                               
         4.2 × 10.sup.-2                                            
                   11         --   V-0  89                                
Example 7                                                                 
Example 10                                                                
         6.1 × 10.sup.-2                                            
                   83         V-0  --   89                                
Comparative                                                               
         7.4 × 10.sup. -2                                           
                   15         V-0  --   87                                
Example 8                                                                 
Example 11                                                                
         6.3 × 10.sup.-2                                            
                   84         V-0  --   90                                
Comparative                                                               
         7.9 × 10.sup.-2                                            
                   11         V-0  --   88                                
Example 9                                                                 
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 *.sup.7 Polycarbonate oligomer of tetrabromobisphenol A                  
 *.sup.8 Epoxy resin containing tetrabromobisphenol A                     
 *.sup.9 Measured according to JISK-7210 (Load: 160 kg/cm.sup.2)          
 *.sup.10 Measured according to JISK-7110 by the use of a sample piece of 
 1/8 inch in thickness.                                                   
 *.sup.11 Vertical Combustion Test was carried out according to           
 Underwriter's Laboratories Subject 94 (UL94)                             
 *.sup.12 Measured according to JISK-7105.                                
       
     
     
       2. The polycarbonate resin composition as defined in claim 1, wherein the halogen-containing flame retarder (B) is a low-molecular weight polycarbonate. 
     
     
       3. The polycarbonate resin composition as defined in claim 1, wherein the halogen-containing flame retarder (B) is an epoxy resin. 
     
     
       4. The polycarbonate resin composition as defined in claim 1, wherein the halogen-containing flame retarder (B) is a low-molecular weight polycarbonate or an epoxy resin and [the halogen-containing flame retarder (B)]comprises tetrahalogenobisphenol. 
     
     
       5. The polycarbonate resin composition as defined in claim 4, wherein the trihalogenophenoxy group is a tribromophenoxy group, the proportion of the repeating unit (I) in the main chain is 2 to 6 mol % and X 1  to X 4  are all bromine atoms. 
     
     
       6. The polycarbonate resin composition as defined in claim 5, wherein the halogen-containing flame retarder (B) comprises tetrahalogenobisphenol A. 
     
     
       7. The polycarbonate resin composition as defined in claim 1, wherein for the polycarbonate (A): the trihalogenophenoxy group is a tribromophenoxy group, the proportion of the repeating unit (I) in the main chain is 2 to 6 mol %, and X 1  to X 4  are all bromine atoms; and the halogen-containing flame retarder (B) comprises m-times a repeating unit (x) of the formula: ##STR15## wherein X 8  to X 11  are each a halogen atom, R is an alkylene group having 2 to 8 carbon atoms, an alkylidene group having 1 to 9 carbon atoms, a carbonyl group, a sulfone group, a sulfur atom or an oxygen atom, and n-times of a repeating unit (y) of formula: ##STR16## wherein R' is an alkylene group having 2 to 8 carbon atoms, an alkylidene group having 1 to 9 carbon atoms, a carbonyl group, a sulfone group, a sulfur atom or an oxygen atom, wherein m is an integer of 0 to 30. n is an integer of 0 to 30, and m+n=1 to 50. 
     
     
       8. The polycarbonate resin composition as defined in claim 7, wherein the repeating unit (x) is a divalent group derived from a reaction product of phosgene and at least one compound selected from the group consisting of 2,2-bis(3,5-dibromo-4-hydroxyphenyl)propane, 2,2-bis(3,5-dichloro-4hydroxyphenyl)propane, bis(3,5-dibromo-4-hydroxyphenyl methane, bis(3,5-dibromo-4-hydroxyphenyl)ether and bis(3,5-dibromohydroxyphenyl)sulfone; and the repeating munit (y) is a divalent group derived from a reaction product of phosgene and at least one compound selected from the group consisting of 2,2-bis(4hydroxyphenyl)propane, bis(4-hydroxyphenyl)methane, bis(4-hydroxyphenyl)sulfone and bis(4-hydroxyphenyl)ether. 
     
     
       9. The polycarbonate resin composition as defined in claim 1, wherein for the polycarbonate (A): the trihalogenophenoxy group is a tribromophenoxy group, the proportion of the repeating unit (I) in the main chain is 2 to 6 mol % and X 1  to X 4  are all bromine atoms and the halogen-containing flame retarder (B) comprises a polymer of the formula: ##STR17## wherein, R 1  is an alkylene group having 2 to 8 carbon atoms, an alkylidene group having 1 to 9 carbon atoms, a carbonyl group, a sulfone group, a sulfur atom or an oxygen atom, R 2  is a hydrogen atom, a methyl group, an epoxypropyl group, a phenyl group, a 2-hydroxypropyl group or an oxygen atom, X 12  to X 15  are each a halogen atom, and p is an integer of 1 to 30. 
     
     
       10. The polycarbonate resin composition as defined in claim 1, wherein for the polycarbonate (A): the trihalogenophenoxy group is a tribromophenoxy group, the proportion of the repeating unit (I) in the main chain is 2 to 6 mol % and X 1  to X 4  are all bromine atoms and the halogen-containing flame retarder is selected from the group consisting of tetrabromobenzene, tetrachlorobenzene, hexabromobenzene, hexachlorobenzene, hexabromobiphenyl, octabromobiphenyl, 2,2'-dichlorobiphenyl, 2,4'-dibromobiphenyl, 2,4'- dichlorobiphenyl, hexabromobiphenyl, triphenylchloride, tetrachlorophthalate, tetrachloroanhydride, tetrabromophthalate, tetrabromophthalic anhydride, tribromophenol, 2,2-bis(3,5-dichlorophenyl)propane, bis(2-chlorophenyl)methane, bis(2,6-dibromophenyl)methane, 1,2-bis(2,6-dichlorophenyl)ethane, 1,1-bis(2-chloro-4-methylphenyl)ethane, 1,1-bis(3,5-dichlorophenyl)ethane, 2,2-bis(3-phenyl-4-bromophenyl)ethane, 2,3-bis(4,6-dichloronaphthyl)propane, 2,2-bis(2,6-dichlorophenyl)pentane, 2,2-bis(2,6-dichlorophenyl)hexane, bis(4-chlorophenyl)methane, bis(3,5-dichlorophenyl) cyclohexylmethane, bis(3-nitro-4bromophenyl)ethane, bis(4-hydroxy-2,6-dichloro-3-methylphenyl)methane, 2,2-bis(3,5-dichloro-4hydroxyphenyl)propane, 2,2-bis(3,5-dibromo-4hydroxyphenyl)propane, 2,2-bis(3-bromo-4-hydroxyphenyl)propane, 2,2-bis(3,5-dibromo-4-hydroxyphenyl)propane diglycydyl ether, decabromodiphenyl ether, octabromodiphenyl ether, hexabromodiphenyl ether, pentabromodiphenyl ether, tetrabromodiphenyl ether, tribromodiphenyl ether, dibromodiphenyl ether, hexachlorodiphenyl ether, pentachlorodiphenyl ether, tetrachlorodiphenyl ether, trichlorodiphenyl ether, and dichlorodiphenyl ether. 
     
     
       11. The polycarbonate resin composition as defined in claim 1, wherein the polycarbonate (A) has a viscosity average molecular weight of 13,000 to 50,000.